The present invention relates to a process for collecting a solid product from a liquid phase or liquid phase-gaseous phase feed stock, and more specifically to a process such that a solid product produced from a liquid phase or liquid phase-gaseous phase mixture having a density greater than a liquid to be supplied is continuously contacted with the liquid countercurrently, and the density relation between the mixture and the liquid is reversed as the latter ascends.
A reaction to produce a reaction product from a liquid phase or liquid phase-gaseous phase reaction system has been well known. As an example, there can be named a reaction to form solid oxamide by blowing cyanogen gas into an aqueous solution of mineral acid and hydrating the same. In this case, it becomes necessary, for obtaining the oxamide as the final product, to remove the acid attached to the oxamide by washing it away with water. A process employed heretofore for such reaction has the disadvantage that not only is a specific washing water required for the washing of oxamide, but also a large quantity of dilute waste acid is produced as by-product, the disposition of which calls for a special operation.
Thus, in an inconsistent reaction wherein a solid product is collected from a liquid phase or liquid phasegaseous phase reaction system, it is not necessarily easy to carry out the reaction on a continuous basis and to continuously remove the solid product from the reaction system. Moreover, it is difficult to remove the solid product in a pure form.
An operation of collecting a solute in the form of solid from a solution by concentrating the solution has also commonly been practiced industrially. According to the conventional operation, however, it has been difficult to remove a substance in such a solution continuously and yet in a washed pure form.
An object of the present invention is to provide a process by which a solid product can be taken out from a liquid phase or liquid phase-gaseous phase feed stock, continuously and yet in a purified form.
Another practical object of the invention is to provide a continuously hydrolyzing process for cyano compounds, such as cyanogen, by which the hydrolysis of a cyano compound, such as cyanogen, whose hyrolysis product is substantially insolutible in water, and the washing of the hydrolysis product with water, can be effected concurrently, and which does not call for a specific washing water for the washing of the hydrolysis product.
Still another practical object of the invention is to provide a process by which a solid substance disolved in a solution, such as brine, can be taken out thereform continuously and yet in a relatiely pure form, without requiring a specific washing liquid.
According to the present invention there is provided a process for collecting a solid product from a liquid phase or liquid phase-gaseous phase feed stock, wherein there is provided a solid forming zone for accommodating a liquid phase or liquid phase-gaseous phase mixture having a density greater than that of a liquid to be fed and a precipitation zone having at its lower portion a feed port for feeding the liquid and a discharge port for discharging the solid reaction product communicating with the solid forming zone at its upper portion, the precipitation zone being provided therein with stirring means by which the solid product and the liquid are caused to contact each other countercurrently, whereby the former is washed with the latter and the density relation between the mixture and the liquid is reversed as the latter moves upwardly.